Many studies have shown that physiological signals arising in the mouth and throat do not produce hunger satiety. My preliminary work shows that food absorbed from and hormones released by the intestines do not produce satiety. In the proposed research, I investigate the importance of humoral and neural signals arising in the stomach and upper duodeum. I also determine how effective are pure chemical meals in stimulating satiety. The meals contain either individual simple sugars, amino acids or fatty acids or fatty acids, I expect these studies to indicate the physical nature of the gut chemoreceptor and to produce enough understanding to influence and enhance the feeling of satiety. Preliminary studies show that rats do not increase their food intake for 5 days when they lose about half their nutrients from the intestines. Metabolic changes affect food intake slowly. In the last two experiments, I investigate the interrelation between short-term satiation signals and long-term weight regulation signals.